The 23-year-old liked a repost of Louis' black-and-white photo, prompting excitement from fans on Twitter. "Friendship never dies," commented one fan, while another wrote: "Zayn liked this and I can't deal, I'm so happy."

Zayn was not the only famous face to like Louis' post. The One Direction star's new girlfriend Danielle Campbell also liked the photo on Instagram, proving she is supportive of Louis' new role as a father.

Unsurprisingly Freddie's proud mum Briana Jungwirth also liked the father-son snap, and posted her own photo of their baby boy on Instagram, adding the caption: "1/21/16. Freddie Reign. Love of my life."

The week-old baby boy looks set to be just as popular as his famous father, with 1.19 million tweets written about Freddie within just five hours of the photo being posted. At the time of writing Louis' picture had already been liked over 410,000 times, with 290,000 retweets from fans.

A number of other fans also created amusing memes about baby Freddie, with one showing a photo of a man crying with the caption: "When you realize that Freddie isn't even a week old yet and is already richer than you'll ever be."

Zayn liked a repost of Louis' photo on Twitter

Louis shared the first photo of Freddie on Wednesday evening. "Meet my little lad Freddie," Louis had captioned the sweet photograph, which showed him shirtless as he cradled his tiny son. He then went on to thank his 21 million Twitter followers, writing: "Thank you so much for all the nice messages."

Louis and his former flame Briana Jungwirth welcomed their son on 21 January, with the new father announcing the happy news on social media. "I'm pleased to say my baby son was born yesterday. He is healthy and pretty amazing. I'm very happy," he tweeted.